read more: http://web-scents.blogspot.com/2014/01/more-security-added-for-your-backbonejs.html

login.js

		login: function (event) {
			event.preventDefault(); // Don't let this button submit the form
			$('.alert').remove(); // Hide any errors on a new submit
			var url = './service/login';
			$('.btn-login').button('loading');
			var formValues = {
				email: $('#tEmail').val(),
				pwd: $('#tPwd').val()
			};

			$.ajax({
				url:url,
				type:'POST',
				dataType:"json",
				data: formValues,
				success:function (data) {					
					if(data.error) {
						$('.alert').remove();
						$('.login-wrap').prepend('<div class="alert alert-warning alert-dismissable"><button type="button" class="close" data-dismiss="alert" aria-hidden="true">&times;</button><strong>Warning!</strong> '+data.error.text+'</div>');
						$('#tEmail').select().focus();
					} else {
						$.ajaxSetup({
							headers: {'X-CSRF-Token': data.token}
						});						
						Backbone.history.navigate("/", { trigger: true, replace: true });						
					}
					$('.btn-login').button('reset');
				}
			});
		}